Inkjet pens and print bars can include one or more printhead dies, each having a plurality of fluid ejection elements on a surface of a silicon substrate. Fluid typically flows to the ejection elements through one or more fluid delivery slots formed in the substrate between opposing substrate surfaces. While such slots effectively deliver fluid to the fluid ejection elements, there are some disadvantages associated with their use. From a cost perspective, for example, fluid delivery slots occupy valuable silicon real estate and add significant slot processing cost. Lower printhead die costs can be achieved in part through shrinking the die size. However, a smaller die size results in a tighter slot pitch and/or slot width in the silicon substrate, which adds excessive assembly costs associated with integrating the smaller die into the inkjet pen. In addition, removing material from the substrate to form an ink delivery slot structurally weakens the printhead die. Thus, when a single printhead die has multiple slots (e.g., to improve print quality and speed in a single color printhead die, or to provide different colors in a multicolor printhead die), the printhead die becomes increasingly fragile with the addition of each slot.
Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements.